Ventricular arrhythmias clinical presentation

Because the severity of symptoms and the absolute serum concentration are poorly correlated in some patients, institution of therapy should be dictated by the clinical scenario. All patients with hypercalcemia should be treated with aggressive rehydration normal saline at 200 to 300 mL/hour is a routine initial fluid prescription. For patients with mild hypocalcemia, hydration alone may provide adequate therapy. The moderate and severe forms of hypercalcemia are more likely to have significant manifestations and require prompt initiation of additional therapy. These patients may present with anorexia, confusion, and/or cardiac manifestations (bradycardia and arrhythmias with ECG changes). Total calcium concentrations greater than 13 mg/dL (3.25 mmol/L) are particularly worrisome, as these levels can unexpectedly precipitate acute renal failure, ventricular arrhythmias, and sudden death. 

Amiodarone may elicit life-threatening side effects in addition to presenting substantial management difh-culties associated with its use. The oral formulation of amiodarone is indicated only for the treatment of life-threatening recurrent ventricular arrhythmias (e.g., recurrent ventricular hbrillation and/or recurrent hemo-dynamicaUy unstable ventricular tachycardia) that have not responded to other potentially effective antiarrhythmic drugs or when alternative interventions could not be tolerated. Despite its efficacy as an antiarrhythmic agent, there is no evidence from clinical trials that the use of amiodarone favorably affects survival. 

III. Clinical presentation. Within minutes to a few hours after ingestion, victims develop profound hypokalemia and skeletal muscle weakness progressing to flaccid paralysis of the limbs and respiratory muscles. Ventricular arrhythmias, hypophosphatemia, rhabdomyolysis, acute renal failure, and coagulopathy may also occur. Gastroenteritis with severe watery diarrhea, mydriasis with impaired visual accommodation, and CNS depression are sometimes present. More often, patients remain conscious even when severely Intoxicated. 

II. Toxic dose. Inhalation or ingestion of as little as 1 mg of fluoroacetate is sufficient to cause serious toxicity. Death is likely after ingestion of mote than 5 mg/kg. Clinical presentation. After a delay of minutes to several hours (in one report coma was delayed 36 hours), manifestations of diffuse cellular poisoning become apparent nausea, vomiting, diarrhea, metabolic acidosis, renal failure, agitation, confusion, seizures, coma, respiratory arrest, pulmonary edema, and ventricular arrhythmias may occur. One case series reported a high incidence of hypocalcemia and hypokalemia. 

Overdose is common amongst users (up to 22% of heavy users report losing consciousness). The desired euphoria and excitement turns to acute fear, with psychotic symptoms, convulsions, hypertension, haemorrhagic storke, tachycardia, arrhythmias, hyperthermia coronary vasospasm (sufficient to present as the acute coronary syndrome with chest pain and myocardial infarction) may occur, and acute left ventricular dysfunction. Treatment is chosen according to the clinical picture (and the known mode of action), from amongst, e.g. haloperidol (rather than chlorpromazine) for mental disturbance diazepam for convulsions a vasodilator, e.g. a calcium channel blocker, for hypertension glyceryl trinitrate for myocardial ischaemia (but not a p-... 

Cardiovascular Essential hypertension and electrocardiographic changes are present (ST-segment depression or flattening, T-wave inversion, and U-wave elevation). Clinical arrhythmias include heart block, atrial flutter, paroxysmal atrial tachycardia, ventricular fibrillation, and digitalis-induced arrhythmias. 

Other less frequent complications of lead extraction include arteriovenous fistulas that present either acutely or in the days following the procedure. Pericardial tamponade could be clinically evident several hours after the procedure. Patients undergoing lead extraction should be monitored for at least 24 h in the intensive care unit, with echocardiography performed electively immediately after the procedure and 6 h later to evaluate the pericardial space and tricuspid valve integrity. Life-threatening arrhythmias such as ventricular tachycardia, torsade de pointes, and ventricular fibrillation are rare but possible complications. 

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